Digital Signal Processing Toolkit

The average value of a sine wave over a complete cycle is :
To avoid aliasing, the minimum sampling frequency for an input signal of 5 Hz should be:
Convolution in time domain is equivalent to __________ in frequency domain.
Which filter should be used to remove noise from a signal?
A signal of frequency 7 Hz is sampled at 10 Hz. What will be the frequency of the signal appearing in the output of the restructured signal?